[PATCH 1/3] core/device: Add function to return child node using name at substring "@"

[PATCH 1/3] core/device: Add function to return child node using name at substring "@"

[Athira Rajeev]

Add a function dt_find_by_name_before_addr() that returns the child node if
it matches till first occurrence at "@" of a given name, otherwise NULL.
This is helpful for cases with node name like: "name@addr". In
scenarios where nodes are added with "name@addr" format and if the
value of "addr" is not known, that node can't be matched with node
name or addr. Hence matching with substring as node name will return
the expected result. Patch adds dt_find_by_name_before_addr() function
and testcase for the same in core/test/run-device.c

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
---
Changelog:
v5 -> v6:
- Addressed review comment from Reza. Instead of using new
  variable for "node", use the node "name" as-is since the
  utility is to check the name before addr. Updated the
  test/run-device.c accordingly

v4 -> v5:
- Addressed review comment from Reza and renamed
  dt_find_by_name_substr to dt_find_by_name_before_addr

v3 -> v4:
- Addressed review comment from Mahesh and added his Reviewed-by.

v2 -> v3:
- After review comments from Mahesh, fixed the code
  to consider string upto "@" for both input node name
  as well as child node name. V2 version was comparing
  input node name and child node name upto string length
  of child name. But this will return wrong node if input
  name is larger than child name. Because it will match
  as substring for child name.
  https://lists.ozlabs.org/pipermail/skiboot/2023-January/018596.html

v1 -> v2:
- Addressed review comment from Dan to update
  the utility funtion to search and compare
  upto "@". Renamed it as dt_find_by_name_substr.

 core/device.c          | 25 +++++++++++++++++++++++++
 core/test/run-device.c | 14 ++++++++++++++
 include/device.h       |  3 +++
 3 files changed, 42 insertions(+)

diff --git a/core/device.c b/core/device.c
index 2de37c741..c22b6b3c3 100644
--- a/core/device.c
+++ b/core/device.c
@@ -395,6 +395,31 @@ struct dt_node *dt_find_by_name(struct dt_node *root, const char *name)
 }
 
 
+struct dt_node *dt_find_by_name_before_addr(struct dt_node *root, const char *name)
+{
+	struct dt_node *child, *match;
+	char *child_node = NULL;
+
+	list_for_each(&root->children, child, list) {
+		child_node = strdup(child->name);
+		if (!child_node)
+			goto err;
+		child_node = strtok(child_node, "@");
+		if (!strcmp(child_node, name)) {
+			free(child_node);
+			return child;
+		}
+
+		match = dt_find_by_name_before_addr(child, name);
+		if (match)
+			return match;
+	}
+
+	free(child_node);
+err:
+	return NULL;
+}
+
 struct dt_node *dt_new_check(struct dt_node *parent, const char *name)
 {
 	struct dt_node *node = dt_find_by_name(parent, name);
diff --git a/core/test/run-device.c b/core/test/run-device.c
index 4a12382bb..fb7a7d2c0 100644
--- a/core/test/run-device.c
+++ b/core/test/run-device.c
@@ -466,6 +466,20 @@ int main(void)
 	new_prop_ph = dt_prop_get_u32(ut2, "something");
 	assert(!(new_prop_ph == ev1_ph));
 	dt_free(subtree);
+
+	/* Test dt_find_by_name_before_addr */
+	root = dt_new_root("");
+	addr1 = dt_new_addr(root, "node", 0x1);
+	addr2 = dt_new_addr(root, "node0_1", 0x2);
+	assert(dt_find_by_name(root, "node@1") == addr1);
+	assert(dt_find_by_name(root, "node0_1@2") == addr2);
+	assert(dt_find_by_name_before_addr(root, "node") == addr1);
+	assert(dt_find_by_name_before_addr(root, "node0_") == NULL);
+	assert(dt_find_by_name_before_addr(root, "node0_1") == addr2);
+	assert(dt_find_by_name_before_addr(root, "node0") == NULL);
+	assert(dt_find_by_name_before_addr(root, "node0_") == NULL);
+	dt_free(root);
+
 	return 0;
 }
 
diff --git a/include/device.h b/include/device.h
index 93fb90ff4..f2402cc4d 100644
--- a/include/device.h
+++ b/include/device.h
@@ -184,6 +184,9 @@ struct dt_node *dt_find_by_path(struct dt_node *root, const char *path);
 /* Find a child node by name */
 struct dt_node *dt_find_by_name(struct dt_node *root, const char *name);
 
+/* Find a child node by name and substring */
+struct dt_node *dt_find_by_name_before_addr(struct dt_node *root, const char *name);
+
 /* Find a node by phandle */
 struct dt_node *dt_find_by_phandle(struct dt_node *root, u32 phandle);
 
-- 
2.31.1

[PATCH 2/3] skiboot: Update IMC code to use dt_find_by_name_before_addr for checking dt nodes

[Athira Rajeev]

The nest IMC (In Memory Collection) Performance Monitoring
Unit(PMU) node names are saved in nest_pmus[] array in the
"hw/imc.c" IMC code. Not all the IMC PMUs listed in the device
tree may be available. Nest IMC PMU names along with their
bit values is represented in imc availability vector.
The nest_pmus[] array is used to remove the unavailable nodes
by checking this vector.

To check node availability, code was using "dt_find_by_substr".
But since the node names have format like: "name@offset",
dt_find_by_name doesn't return the expected result. Fix this
by using dt_find_by_name_before_addr. Also, update the char array
to use correct node names.

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
---
Changelog:
v4 -> v5:
- Addressed review comment from Reza and renamed
  dt_find_by_name_substr to dt_find_by_name_before_addr

v3 -> v4:
- Addressed review comment from Mahesh and added his Reviewed-by
  for patch 1.

v2 -> v3:
- After review comments from Mahesh, fixed the code
  to consider string upto "@" for both input node name
  as well as child node name. V2 version was comparing
  input node name and child node name upto string length
  of child name. But this will return wrong node if input
  name is larger than child name. Because it will match
  as substring for child name.
  https://lists.ozlabs.org/pipermail/skiboot/2023-January/018596.html

v1 -> v2:
- Addressed review comment from Dan to update
  the utility funtion to search and compare
  upto "@". Renamed it as dt_find_by_name_substr.

 hw/imc.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/hw/imc.c b/hw/imc.c
index 97e0809f0..73f25dae8 100644
--- a/hw/imc.c
+++ b/hw/imc.c
@@ -67,14 +67,14 @@ static char const *nest_pmus[] = {
 	"mba5",
 	"mba6",
 	"mba7",
-	"cen0",
-	"cen1",
-	"cen2",
-	"cen3",
-	"cen4",
-	"cen5",
-	"cen6",
-	"cen7",
+	"centaur0",
+	"centaur1",
+	"centaur2",
+	"centaur3",
+	"centaur4",
+	"centaur5",
+	"centaur6",
+	"centaur7",
 	"xlink0",
 	"xlink1",
 	"xlink2",
@@ -412,7 +412,7 @@ static void disable_unavailable_units(struct dt_node *dev)
 	for (i = 0; i < ARRAY_SIZE(nest_pmus); i++) {
 		if (!(PPC_BITMASK(i, i) & avl_vec)) {
 			/* Check if the device node exists */
-			target = dt_find_by_name(dev, nest_pmus[i]);
+			target = dt_find_by_name_before_addr(dev, nest_pmus[i]);
 			if (!target)
 				continue;
 			/* Remove the device node */
-- 
2.31.1

[PATCH 3/3] skiboot: Update IMC PMU node names for power10

[Athira Rajeev]

The nest IMC (In Memory Collection) Performance Monitoring
Unit(PMU) node names are saved as "struct nest_pmus_struct"
in the "hw/imc.c" IMC code. Not all the IMC PMUs listed in
the device tree may be available. Nest IMC PMU names along with
their bit values is represented in imc availability vector.
This struct is used to remove the unavailable nodes by checking
this vector.

For power10, the imc_chip_avl_vector ie, imc availability vector
( which is a part of the IMC control block structure ), has
change in mapping of units and bit positions. Hence rename the
existing nest_pmus array to nest_pmus_p9 and add entry for power10
as nest_pmus_p10.

Also the avl_vector has another change in bit positions 11:34. These
bit positions tells the availability of Xlink/Alink/CAPI. There
are total 8 links and three bit field combination says which link
is available. Patch implements all these change to handle
nest_pmus_p10.

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
---
Changelog:
v5 -> v6:
- Addressed review comment from Reza by using PPC_BIT
  instead of PPC_BITMASK

v4 -> v5:
- Addressed review comment from Reza and renamed
  dt_find_by_name_substr to dt_find_by_name_before_addr

v3 -> v4:
- Addressed review comment from Mahesh and added his Reviewed-by
  for patch 1.

v2 -> v3:
- After review comments from Mahesh, fixed the code
  to consider string upto "@" for both input node name
  as well as child node name. V2 version was comparing
  input node name and child node name upto string length
  of child name. But this will return wrong node if input
  name is larger than child name. Because it will match
  as substring for child name.
  https://lists.ozlabs.org/pipermail/skiboot/2023-January/018596.html

v1 -> v2:
- Addressed review comment from Dan to update
  the utility funtion to search and compare
  upto "@". Renamed it as dt_find_by_name_substr.

 hw/imc.c | 196 ++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 186 insertions(+), 10 deletions(-)

diff --git a/hw/imc.c b/hw/imc.c
index 73f25dae8..9f59348ad 100644
--- a/hw/imc.c
+++ b/hw/imc.c
@@ -49,7 +49,7 @@ static unsigned int *htm_scom_index;
  * imc_chip_avl_vector(in struct imc_chip_cb, look at include/imc.h).
  * nest_pmus[] is an array containing all the possible nest IMC PMU node names.
  */
-static char const *nest_pmus[] = {
+static const char *nest_pmus_p9[] = {
 	"powerbus0",
 	"mcs0",
 	"mcs1",
@@ -104,6 +104,67 @@ static char const *nest_pmus[] = {
 	/* reserved bits : 51 - 63 */
 };
 
+static const char *nest_pmus_p10[] = {
+	"pb",
+	"mcs0",
+	"mcs1",
+	"mcs2",
+	"mcs3",
+	"mcs4",
+	"mcs5",
+	"mcs6",
+	"mcs7",
+	"pec0",
+	"pec1",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"NA",
+	"phb0",
+	"phb1",
+	"phb2",
+	"phb3",
+	"phb4",
+	"phb5",
+	"ocmb0",
+	"ocmb1",
+	"ocmb2",
+	"ocmb3",
+	"ocmb4",
+	"ocmb5",
+	"ocmb6",
+	"ocmb7",
+	"ocmb8",
+	"ocmb9",
+	"ocmb10",
+	"ocmb11",
+	"ocmb12",
+	"ocmb13",
+	"ocmb14",
+	"ocmb15",
+	"nx",
+};
+
 /*
  * Due to Nest HW/OCC restriction, microcode will not support individual unit
  * events for these nest units mcs0, mcs1 ... mcs7 in the accumulation mode.
@@ -371,7 +432,7 @@ static void disable_unavailable_units(struct dt_node *dev)
 	uint64_t avl_vec;
 	struct imc_chip_cb *cb;
 	struct dt_node *target;
-	int i;
+	int i, j;
 	bool disable_all_nests = false;
 	struct proc_chip *chip;
 
@@ -409,14 +470,129 @@ static void disable_unavailable_units(struct dt_node *dev)
 			avl_vec = (0xffULL) << 56;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(nest_pmus); i++) {
-		if (!(PPC_BITMASK(i, i) & avl_vec)) {
-			/* Check if the device node exists */
-			target = dt_find_by_name_before_addr(dev, nest_pmus[i]);
-			if (!target)
-				continue;
-			/* Remove the device node */
-			dt_free(target);
+	if (proc_gen == proc_gen_p9) {
+		for (i = 0; i < ARRAY_SIZE(nest_pmus_p9); i++) {
+			if (!(PPC_BIT(i) & avl_vec)) {
+				/* Check if the device node exists */
+				target = dt_find_by_name_before_addr(dev, nest_pmus_p9[i]);
+				if (!target)
+					continue;
+				/* Remove the device node */
+				dt_free(target);
+			}
+		}
+	} else if (proc_gen == proc_gen_p10) {
+		int val;
+		char name[8];
+
+		for (i = 0; i < 11; i++) {
+			if (!(PPC_BIT(i) & avl_vec)) {
+				/* Check if the device node exists */
+				target = dt_find_by_name_before_addr(dev, nest_pmus_p10[i]);
+				if (!target)
+					continue;
+				/* Remove the device node */
+				dt_free(target);
+			}
+		}
+
+		for (i = 35; i < 41; i++) {
+			if (!(PPC_BIT(i) & avl_vec)) {
+				/* Check if the device node exists for phb */
+				for (j = 0; j < 3; j++) {
+					snprintf(name, sizeof(name), "phb%d_%d", (i-35), j);
+					target = dt_find_by_name_before_addr(dev, name);
+					if (!target)
+						continue;
+					/* Remove the device node */
+					dt_free(target);
+				}
+			}
+		}
+
+		for (i = 41; i < 58; i++) {
+			if (!(PPC_BIT(i) & avl_vec)) {
+				/* Check if the device node exists */
+				target = dt_find_by_name_before_addr(dev, nest_pmus_p10[i]);
+				if (!target)
+					continue;
+				/* Remove the device node */
+				dt_free(target);
+			}
+		}
+
+		for (i = 0; i < 8; i++) {
+			val = ((avl_vec & (0x7ULL << (29 + (3 * i)))) >> (29 + (3 * i)));
+			switch (val) {
+			case 0x5: //xlink configured and functional
+
+				snprintf(name, sizeof(name), "alink%1d", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				snprintf(name, sizeof(name), "otl%1d_0", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				snprintf(name, sizeof(name), "otl%1d_1", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				break;
+			case 0x6: //alink configured and functional
+
+				snprintf(name, sizeof(name), "xlink%1d", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				snprintf(name, sizeof(name), "otl%1d_0", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				snprintf(name, sizeof(name), "otl%1d_1", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+				break;
+
+			case 0x7: //CAPI configured and functional
+				snprintf(name, sizeof(name), "alink%1d", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				snprintf(name, sizeof(name), "xlink%1d", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+				break;
+			default:
+				snprintf(name, sizeof(name), "xlink%1d", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				snprintf(name, sizeof(name), "alink%1d", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				snprintf(name, sizeof(name), "otl%1d_0", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+
+				snprintf(name, sizeof(name), "otl%1d_1", (7-i));
+				target = dt_find_by_name_before_addr(dev, name);
+				if (target)
+					dt_free(target);
+				break;
+			}
 		}
 	}
 
-- 
2.31.1

Re: [PATCH 1/3] core/device: Add function to return child node using name at substring "@"

[Reza Arbab]

Hi Athira,

On Thu, Sep 14, 2023 at 10:02:04PM +0530, Athira Rajeev wrote: 
>+struct dt_node *dt_find_by_name_before_addr(struct dt_node *root, const char *name)
>+{
>+	struct dt_node *child, *match;
>+	char *child_node = NULL;
>+
>+	list_for_each(&root->children, child, list) {
>+		child_node = strdup(child->name);
>+		if (!child_node)
>+			goto err;
>+		child_node = strtok(child_node, "@");
>+		if (!strcmp(child_node, name)) {
>+			free(child_node);
>+			return child;
>+		}
>+
>+		match = dt_find_by_name_before_addr(child, name);
>+		if (match)
>+			return match;

When the function returns on this line, child_node is not freed.

>+	}
>+
>+	free(child_node);
>+err:
>+	return NULL;
>+}

I took at stab at moving free(child_node) inside the loop, and ended up 
with this:

struct dt_node *dt_find_by_name_before_addr(struct dt_node *root, const char *name)
{
	struct dt_node *child, *match = NULL;
	char *child_name = NULL;

	list_for_each(&root->children, child, list) {
		child_name = strdup(child->name);
		if (!child_name)
			return NULL;

		child_name = strtok(child_name, "@");
		if (!strcmp(child_name, name))
			match = child;
		else
			match = dt_find_by_name_before_addr(child, name);

		free(child_name);
		if (match)
			return match;
	}

	return NULL;
}

Does this seem okay to you? If you agree, no need to send another 
revision, I can just fixup during commit. Let me know.

>diff --git a/core/test/run-device.c b/core/test/run-device.c
>index 4a12382bb..fb7a7d2c0 100644
>--- a/core/test/run-device.c
>+++ b/core/test/run-device.c
>@@ -466,6 +466,20 @@ int main(void)
> 	new_prop_ph = dt_prop_get_u32(ut2, "something");
> 	assert(!(new_prop_ph == ev1_ph));
> 	dt_free(subtree);
>+
>+	/* Test dt_find_by_name_before_addr */
>+	root = dt_new_root("");
>+	addr1 = dt_new_addr(root, "node", 0x1);
>+	addr2 = dt_new_addr(root, "node0_1", 0x2);
>+	assert(dt_find_by_name(root, "node@1") == addr1);
>+	assert(dt_find_by_name(root, "node0_1@2") == addr2);
>+	assert(dt_find_by_name_before_addr(root, "node") == addr1);
>+	assert(dt_find_by_name_before_addr(root, "node0_") == NULL);

This line appears twice. As above, can fix during commit, so no need for 
a new patch.

>+	assert(dt_find_by_name_before_addr(root, "node0_1") == addr2);
>+	assert(dt_find_by_name_before_addr(root, "node0") == NULL);
>+	assert(dt_find_by_name_before_addr(root, "node0_") == NULL);
>+	dt_free(root);
>+
> 	return 0;
> }
>

-- 
Reza Arbab

Re: [PATCH 1/3] core/device: Add function to return child node using name at substring "@"

[Athira Rajeev]

> On 15-Sep-2023, at 8:00 PM, Reza Arbab <arbab@linux.ibm.com> wrote:
> 
> Hi Athira,
> 
> On Thu, Sep 14, 2023 at 10:02:04PM +0530, Athira Rajeev wrote: 
>> +struct dt_node *dt_find_by_name_before_addr(struct dt_node *root, const char *name)
>> +{
>> + struct dt_node *child, *match;
>> + char *child_node = NULL;
>> +
>> + list_for_each(&root->children, child, list) {
>> + child_node = strdup(child->name);
>> + if (!child_node)
>> + goto err;
>> + child_node = strtok(child_node, "@");
>> + if (!strcmp(child_node, name)) {
>> + free(child_node);
>> + return child;
>> + }
>> +
>> + match = dt_find_by_name_before_addr(child, name);
>> + if (match)
>> + return match;
> 
> When the function returns on this line, child_node is not freed.
> 
>> + }
>> +
>> + free(child_node);
>> +err:
>> + return NULL;
>> +}
> 
> I took at stab at moving free(child_node) inside the loop, and ended up with this:
> 
> struct dt_node *dt_find_by_name_before_addr(struct dt_node *root, const char *name)
> {
> struct dt_node *child, *match = NULL;
> char *child_name = NULL;
> 
> list_for_each(&root->children, child, list) {
> child_name = strdup(child->name);
> if (!child_name)
> return NULL;
> 
> child_name = strtok(child_name, "@");
> if (!strcmp(child_name, name))
> match = child;
> else
> match = dt_find_by_name_before_addr(child, name);
> 
> free(child_name);
> if (match)
> return match;
> }
> 
> return NULL;
> }
> 
> Does this seem okay to you? If you agree, no need to send another revision, I can just fixup during commit. Let me know.

Hi Reza,

Sure, Change looks good. Thanks for the change and fixup.

Thanks
Athira
> 
>> diff --git a/core/test/run-device.c b/core/test/run-device.c
>> index 4a12382bb..fb7a7d2c0 100644
>> --- a/core/test/run-device.c
>> +++ b/core/test/run-device.c
>> @@ -466,6 +466,20 @@ int main(void)
>> new_prop_ph = dt_prop_get_u32(ut2, "something");
>> assert(!(new_prop_ph == ev1_ph));
>> dt_free(subtree);
>> +
>> + /* Test dt_find_by_name_before_addr */
>> + root = dt_new_root("");
>> + addr1 = dt_new_addr(root, "node", 0x1);
>> + addr2 = dt_new_addr(root, "node0_1", 0x2);
>> + assert(dt_find_by_name(root, "node@1") == addr1);
>> + assert(dt_find_by_name(root, "node0_1@2") == addr2);
>> + assert(dt_find_by_name_before_addr(root, "node") == addr1);
>> + assert(dt_find_by_name_before_addr(root, "node0_") == NULL);
> 
> This line appears twice. As above, can fix during commit, so no need for a new patch.
> 
>> + assert(dt_find_by_name_before_addr(root, "node0_1") == addr2);
>> + assert(dt_find_by_name_before_addr(root, "node0") == NULL);
>> + assert(dt_find_by_name_before_addr(root, "node0_") == NULL);
>> + dt_free(root);
>> +
>> return 0;
>> }
>> 
> 
> -- 
> Reza Arbab

Re: [PATCH 1/3] core/device: Add function to return child node using name at substring "@"

[Reza Arbab]

On Thu, Sep 14, 2023 at 10:02:04PM +0530, Athira Rajeev wrote:
>Add a function dt_find_by_name_before_addr() that returns the child node if
>it matches till first occurrence at "@" of a given name, otherwise NULL.
>This is helpful for cases with node name like: "name@addr". In
>scenarios where nodes are added with "name@addr" format and if the
>value of "addr" is not known, that node can't be matched with node
>name or addr. Hence matching with substring as node name will return
>the expected result. Patch adds dt_find_by_name_before_addr() function
>and testcase for the same in core/test/run-device.c

Series applied to skiboot master with the fixup we discussed.

-- 
Reza Arbab

Re: [PATCH 1/3] core/device: Add function to return child node using name at substring "@"

[Athira Rajeev]

> On 18-Sep-2023, at 7:42 PM, Reza Arbab <arbab@linux.ibm.com> wrote:
> 
> On Thu, Sep 14, 2023 at 10:02:04PM +0530, Athira Rajeev wrote:
>> Add a function dt_find_by_name_before_addr() that returns the child node if
>> it matches till first occurrence at "@" of a given name, otherwise NULL.
>> This is helpful for cases with node name like: "name@addr". In
>> scenarios where nodes are added with "name@addr" format and if the
>> value of "addr" is not known, that node can't be matched with node
>> name or addr. Hence matching with substring as node name will return
>> the expected result. Patch adds dt_find_by_name_before_addr() function
>> and testcase for the same in core/test/run-device.c
> 
> Series applied to skiboot master with the fixup we discussed.
> 
> -- 
> Reza Arbab

Thanks Reza for picking up the patchset

Athira